No abstract available

[en] Commonly, chaff cartridge release the chaff based on detonating the dynamite or blasting form projectile. In order to improve the scatter effect of chaff, a novel technique of chaff release is proposed, which is be carried by a given carrier revolving around an axis at high speed. And the model of chaff motion in the phase of dispersing rapidly is established on the basis of the analysing the influence of resistance, gravity and viscous force. Simulation instance show that the method based on revolving carrier is efficacious, and some useful revelation can be elicited from the simulation. The research in this paper has great significance for the research and engineering implementation of gun launched chaff jamming projectile. (paper)

No abstract available

[en] The paper is focused on 2,4,6,4',6',2''4''6''-octanitro[l,1',3',1'']terphenyl (ONT), 2,2',2''4,4',4''6,6',6''-nonanitro[l,l',3',1'']terphenyl (NONA), 2,4,6-tris(2,4,6-trinitrophenyl)-1,3,5-triazine (TPT), N,N-bis(2,4-dinitrophenyl)-2,4,6-trinitroaniline (NTFA), 1,3,7,9-tetranitro[l,2,3]benzotriazolo[2,l-a] [l,2,3]benzotriazole-5,11-diium6,12-diide (TACOT-Z), 2,2',4,4',6,6'-hexanitrobiphenyl (HNB), 1,3-dinitrobenzene (1,3-DNB), 1,3,5-trinitrobenzene (TNB) and 2,4,6-triamino-1,3,5-trinitrobenzene (TATB). The initiation reactivity of these substances has been studied by means of the data obtained from non-isothermal differential thermal analysis (DTA), their ignition temperatures, impact sensitivity, the data obtained from the Russian manometric method, the detonation characteristics, DFT B3LYP/6-31G(d,p) charges on the nitrogen atoms of nitro group q ^N(NO₂) and net charges of these groups Q(NO₂). For comparison, also the data published and calculated on 2,2',2'',2''',4,4',4'',4''',6,6',6'',6'''-dodecanitro[l,3',1',1''] quaterphenyl (DODECA) have been included. The paper specifies and discusses the relationships between the results of various methods used, inclusive between their outputs and charges and net charges of the primarily reacting nitro groups in the initiations. Relations of these charges to the characteristics of thermal reactivity, detonation and impact sensitivity confirm presumption about the identity of primary chemical processes in the initiation by heat (low-temperature thermolysis), shock and impact. The technologically most attractive substances can be ordered in the sequence TACOT ≥ ONT > TPT > NONA >> NTFA > TATB according to their decreasing thermal stability

No abstract available

No abstract available

No abstract available

[en] We investigate the (002) lattice strain evolution of triaminotrinitrobenzene (TATB) grains inside one TATB-based plastic bonded explosive (PBX) through the in-situ neutron diffraction. By comparing the untreated specimen with the thermal-treated one, it is found that the volume-average response of measured TATB grains remains nearly elastic during quasi-static uniaxial compression. The observed changes in TATB (002) lattice strains correlate tightly with the evolution of damage. A damage parameter defined by the macroscopically determined residual strain is further used to describe the damage degree of PBX, which suggests that the compressive behavior of TATB-based PBX is significantly influenced by the damage evolution. (authors)

[en] As the nation's nuclear weapons age and the demands placed on them change, significant challenges face the nuclear stockpile. Risks include material supply issues, ever-increasing lifecycle costs, and loss of technical expertise across the weapons complex. For example, non-nuclear materials are becoming increasingly difficult to replace because manufacturing methods and formulations have evolved in such a way as to render formerly available materials unprofitable, unsafe, or otherwise obsolete. Subtle formulation changes in available materials that occur without the knowledge of the weapons community for proprietary reasons have frequently affected the long-term performance of materials in the nuclear weapon environment. Significant improvements in performance, lifetime, or production cost can be realized with modern synthesis, modeling, and manufacturing methods. For example, there are currently supply and aging issues associated with the insensitive high explosive formulations LX-17 and PBX 9502 that are based on triaminotrinitrobenzene (TATB) and Kel-F, neither of which are commercially available today. Assuring the reliability of the stockpile through surveillance and regularly scheduled Life Extension Programs is an increasingly expensive endeavor. Transforming our current stockpile surveillance--a system based on destructive testing of increasingly valuable assets--to a system based on embedded sensors has a number of potential advantages that include long-term cost savings, reduced risk associated with asset transportation, state-of-health assessments in the field, and active management of the stockpile.

[en] Vibrational properties of gas-phase TATB molecule and TATB crystal are investigated by means of density functional theory with gradient correction. The intramolecular geometry of TATB crystal agrees reasonably with experiment. The vibrational frequencies of TATB molecule and crystal are computed and the internal modes are analyzed. The simulated infrared spectra of the gas-phase TATB molecule reproduce the experimental spectra fairly well. The structure and vibrational properties of the TATB molecule in gas phase and in crystal phase are compared and discussed in terms of intermolecular interaction